[Graham]

Hi Mark,
Great to see your post on here. 
To answer your question yes there will be an option on the application form for a 3 car entry ( but they will be limited to a few) Based on a first declaration basis.

But as you mentioned “scratch building a chassis” the Events 1&2 are limited to either Revoslot Standard or Plastic chassis based cars. Only Event 3 is open to plastic, Revoslot and scratchbuild metal chassis constructed cars.